A young woman approaches the Boy Detectives' Club and asks them to find the intended recipient of a series of threat letters her boyfriend made. They accept the job and begin to tail her boyfriend. Meanwhile Kobayashi, after missing his chance to return Hanasaki's dropped wallet, uses it to buy a desperately needed meal. Hanasaki finds out by checking his electronic money usage history, and he convinces Kobayashi to join him on the current investigation in a second attempt to get him to join the club...
but the average fee is 100,000 yen 
per three hours of investigation.
aber die durchschnittliche Gebühr
beträgt 100.000 Yen für 3 Stunden.
pero la tarifa base es de 100 mil yenes
cada tres horas de investigación.
mas a média é de 100 mil ienes
por três horas de investigação.